1. Field of the Invention
The invention generally relates to a retractable screen and frame assembly for covering and uncovering a door or a window opening.
2. Description of the Related Art
Traditional door or window openings are covered and uncovered with a screen and frame assembly that rolls. The opening is bounded by a frame and the assembly includes a pair of opposing tracks that are adjacent the frame in spaced and parallel relationship. The screen includes a surround having four sides and wheels on two opposing sides of the surround that correspond to the opposing tracks. When the screen is installed to the tracks inside the opening, the wheels allow the screen to roll along the tracks across the opening. However, with this type of assembly, the screen has the tendency to bind as it is rolled along the tracks. Additionally, the wheels on the surround tend to come off of the tracks, causing the screen to fall out of the frame.
Another type of screen and frame assembly that has been used is a retractable screen and frame assembly. An example of a conventional retractable screen and frame assembly is disclosed in U.S. Pat. No. 6,814,127 (the '127 patent). The '127 patent discloses an opening which is bounded by an upper track and a bottom track in spaced relationship. The tracks include a powder coat finish that reduces friction. Each track includes a rail with a round cross-section. The retractable screen assembly includes a canister, a screen cloth, and a control bar. The screen cloth is connected between the canister and the control bar. The canister includes a roller assembly for winding and unwinding the screen cloth into and out of the canister. The control bar has an upper end and a lower end. A spacer and a lower glide are disposed at the lower end. The spacer defines two holes and the spacer engages the lower end of the control bar. A pair of posts are formed on the lower glide. The posts of the lower glide are slidably inserted into the holes of the spacer. While the spacer engages the lower end of the control bar, the lower glide slides axially with respect to the end of the control bar through the holes in the spacer. The spacer is passive and therefore does not actively react between the lower glide and the lower end of the control bar. An upper glide is affixed to the upper end of the control bar. Both glides define a channel that is shaped to mate with the cross-section rails on the tracks to slidably retain the glides to the corresponding tracks. Therefore, the control bar and the upper glide are slidably engaged and suspended from the upper track and the lower glide is slidably engaged with the lower track. As the control bar and the glides slide along the tracks and the upper glide and the control bar are suspended from the upper track, the lower glide moves axially with respect to the control bar by virtue of the spacer. As the tracks vary by distance, the upper glide and the control bar follow the upper track and the lower glide follows the lower track. Any distance between the tracks is translated into the lower glide, following the lower track, to move toward or away from the lower end of the control bar. Therefore, the axial movement between the lower glide and the control bar requires the upper and lower glides to be affixed to their respective tracks. The axial movement of the lower glide with respect the spacers is aided by forming the glide from silicone, Teflon® impregnated acetal, or other friction reducing materials. However, application of these types of coatings is expensive due to the materials, time, and steps added to the assembly process.
Accordingly, it would be advantageous to provide a sliding screen assembly that does not require the use of special materials to form the components of the sliding screen assembly, i.e., silicone or Teflon® impregnated acetal, or require special processing steps, i.e., a powder coat finish. The use of the special materials and/or special processing steps adds time and cost to the manufacture of the sliding screen assembly.